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Hormesis - Biology redefined - Getting Stronger from Adversity

Hormesis - Biology redefined - Getting Stronger from Adversity

Hormesis is a biological phenomenon which has puzzled scientists for decades. It essentially means that the stressor keeps the organism strong. It pertains to the study of benefits of exposure to toxins (Sounds odd, isn’t it!) such as radiation or mercury.

Take the example of exercise - say running. It is certainly beneficial in the long run. But see for a moment the physiological processes triggered with the activity of running. It causes the heart rate and blood pressure to skyrocket. Muscles and bones get burdened and strained. Metabolism shoots up. What is alarming is that this activity of running increases the production of free radicals - which are considered as harmful molecules. What is more ironic is that the antioxidant supplements (which flood the racks of pharmacies and supermarkets) actually interfere with the process of getting stronger and healthier from exercise. They in fact cancel out some of the benefits you get from exercise. But the end result of all such negative and harmful substances generated from the activity of exercise is beneficial. This is explained by the mysterious process of Hormesis.

Take another example of well known and age old poison arsenic. It is a sure killer. When scientists gave a fixed low dose to worm C.elegans, they actually lived longer than usual. Surprised? Wait, more shocks are in store. Not only do they live longer, these worms become more resistant to stress from heat and other poisonous substances.This is a classic case of Hormesis. While arsenic is poisonous, low doses function as a survivable stressor that makes the worms raise their defensive capabilities.

Take the example of the harmful biological oxidation process. Scientists have experimented with pro-oxidants. It is the opposite of antioxidants. It actually increases oxidative stress. They have given pro-oxidant herbicide paraquat to worm C.elegans. Contrary to the conventional medical wisdom (of pro-oxidant causing harm to organisms), it resulted in the increasing their lifespan. Interestingly, if the Scientists also gave the worms antioxidants (which are supposed to be beneficial to health), then the worms did not live longer than usual. This makes the whole biological science topsy turvy! In other words, our enemy substances become our friend (beneficial to health) and our friendly substances become our enemy (harmful to health) in the battle for survival within a specific zone of tolerance. Outside this zone, they again resume their assigned role of friend and enemy. This may sound insane, bizarre - but it is a proven observation with well accepted scientific experiments done again and again.

It is long established that free radicals cause oxidative stress in our body. They are the cause of our aging process. Scientists got curious when they learned that the long-lived birds don’t have less oxidative stress than their short lived brothers. Also the naked mole-rats have the same amount of oxidative stress as mice, though these rats live much longer than the mice. They handle the stress arising from exposure to DNA-harming chemicals, low oxygen levels, ingestion of heavy metals, or exposure to extreme heat in a much better way than mice.

Take another example of radiation. Human exposure to radiation is long considered to be carcinogenic. But one incident in Taiwan around the year 1983 proved to be exactly opposite of this established medical theory. In that incident the construction steel was (then unknown to authorities) contaminated with the radioactive cobalt-60 which was used to build over 1,700 apartments. But it was not noticed for a long many years. Scientists were baffled with the observation of the BENEFICIAL effect of this low dose radiation. This experience indicated that chronic exposure of the whole body to low-dose-rate radiation, even accumulated over a period to a high annual dose, may be beneficial to human health. Approximately 10,000 people occupied these buildings and received an average radiation dose of 0.4 Sv, unknowingly, during a 9–20 year period. They did not suffer a higher incidence of cancer mortality, as the LNT theory (Linear no-threshold) would predict. On the contrary, the incidence of cancer deaths in this population was greatly reduced—to about 3 percent of the incidence of spontaneous cancer death in the general Taiwan public. In addition, the incidence of congenital malformations was also substantially reduced—to about 7 per cent of the incidence in the general public. In other words, these residents actually BENEFITED substantially from the low radiation dose rather than suffered from it. This again is the clear example of hormesis.

It is also observed that Among American shipyard workers who work with nuclear submarines have a lower mortality rate than workers at normal shipyards. Similarly, in the general US population, those living in areas with higher-than-usual background radiation live longer than average. Radiologists who are exposed to ionizing radiation live longer than other doctors and have a lower risk of cancer.

The process of hormesis is not restricted just to the area of exposures to external agents or environmental conditions. Hormesis is in reality integral to the normal physiological functions of cells and organisms. When neurons are exposed to the excitatory neurotransmitter glutamate during their normal activity, it has the effect of energetic and oxidative stress. This is accompanied by the activation of hormetic pathways. These pathways actually help the neurons cope with more severe stress. At the same time when there is excessive activation of glutamate receptors, the neurons get killed. This process is called excitotoxicity. To put it simply, little bad is good while more bad kills. And we do not have a demarcating line between this ‘little bad’ and ‘more bad’.

Can we then start hormesis as a treatment for good health? Can we develop ‘hormesis therapy’? The key takeaway is that the scientists have not been able to fix EXACT quantity of beneficial dosage of toxin to be beneficial with hormesis. We can only surmise that the secret to a long life is not to live without difficult times, but to be able to withstand the onslaught.

Because of the limitation in testing toxins (radiation,arsenic etc) on humans, scientists will never be able to measure the exact quantity of it which will be beneficial through the system of hormesis. There will only be guesses as to how this system works. In other words, though we know the beneficial process of hormesis, we can not medically start practicing it. The scientists have not discovered a sure key behind this process. They know the end result, but they can not have a grip with the actual root cause of it.

Nature has given us an elemental mechanism of hormesis. But the humans are not able to effectively use it to their advantage, because of the gray area of the threshold of tolerance. To ascertain this threshold on humans means to get killed in the process of trials. So it seems that this very useful and miraculous process of hormesis will forever remain outside the medical therapeutic use.

Sri Anand Yoga (SAY) uses this process of hormesis to our full benefit through its various yogic practices and way of life. One of them is the Playful Engagement with Life. It is explained separately elsewhere. In SAY we do not work any magic, going outside the natural processes. We remain within the natural realm. We only use the natural processes in such a way that we exploit its maximum potential. In SAY our routine daily activities generate astonishing beneficial effects on our health and well being. One of the key elements of SAY practice is the psycho-spiritual aspects of hormesis.


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